Devices for removing NOx from the exhaust gas of an internal combustion engine may be embodied as traps for removing NOx from the exhaust gas by “trapping” the NOx as the exhaust gas advances therethrough. Such a NOx trap must be periodically regenerated to purge the trap of the trapped NOx. To do so, the NOx trap periodically undergoes a catalytic reaction in which the trapped NOx is converted to less harmful gases that are subsequently exhausted from the trap.
Reductant fluids may be utilized to facilitate such regeneration of the trap. Reductant fluids may take a number of different forms. For example, liquids such as untreated diesel fuel may be used as a reductant fluid. Alternatively, gases such as hydrogen gas or carbon monoxide gas may also be used as a reductant fluid.
One way to generate a gaseous reductant fluid is by use of an onboard fuel reformer. A fuel reformer is operated to reform a hydrocarbon fuel into a reformate gas. In the case of an onboard fuel reformer, such as a fuel reformer associated with a vehicle or a stationary power generator, the reformate gas produced by the fuel reformer may be utilized as the reductant fluid to regenerate or otherwise condition an emission abatement device associated with an internal combustion engine such as a NOx trap.